This invention relates in general to lighting fixtures and more specifically, to a system for assembling a translucent or transparent elements into a three dimensional array. Modern, high fashion lighting fixtures for home or business use can be formed by suspending a three dimensional array of crystals or pieces of some other translucent material organized about, or with, a light source or sources. The most common form is a set of crystal, glass or plastic elements that surround a set of electric light bulbs at the center of the fixture with the entire fixture suspended by a chain or cable from a ceiling. (In this application, these elements will be referred to as "crystals" even though they may not be formed of crystal.) The individual crystal pieces are typically attached to a rigid frame which is attached to the chain or cable. The frame can take a wide variety of forms, such as a central vertical member with radial branches, but the most common form is a closed loop metal member, or a set of vertically spaced such members that support the crystals. The assembly system to mount the crystals on the fixture must serve a variety of design objectives, but central to the success of the system is the ability to hold the crystals in place during mechanical jostling, as during hanging, cleaning or maintenance, and the ability to accurately and reliably secure the crystals in a predetermined location and with a predetermined orientation.
Heretofore, there have been two general approaches to the assembly of the crystals for such a fixture. One approach is to assemble the crystals and the bracket as a single unit at the factory. This avoids assembly after shipment and can lead to a "cleaner" design than with on site assembly, but there are increased manufacturing costs to assemble the complete fixture as a permanent unit, it is more costly to ship the fully assembled fixture, and there is an increased likelihood of breakage during shipment. To avoid these problems it is also known to weld, rivet, screw, glue or otherwise permanently secure a metal piece to the bracket. The crystals can be packaged separately for shipment but are secured to the metal pieces as by snap fasteners or wire. This approach allows the crystal to be shipped with a lower likelihood of damage than if pre-assembled, and offers a compact shipping configuration. However, the welding, riveting, screwing or other permanent assembly technique increases the cost of manufacture and the attachment can be unattractive.
It is also possible to assemble crystals to a bracket on site using relatively simple and inexpensive wire hooks, loops and the like. Besides being relatively unaesthetic in appearance, such a system does not provide a high degree of stability and it can be difficult to locate and orient the crystals with accuracy and reliability, particularly where the crystals are generally planar and their orientation and location is important to achieving the overall design of the fixture. Also, it is a time consuming process that involves a great deal of handling of the crystals by the assembler. The risks of breakage of the crystals. Especially in the hands of an unskilled installer, are substantial.
It is therefore a principal object of this invention to provide an assembly system for a gravity-suspended multi-crystal fixture which allows rapid on-site assembly without special tools or skill, and which also accurately and reliably positions and orients the crystals in a predetermined three dimensional array.
It is a further principal object of this invention to provide such an assembly system which mounts the crystals with a high degree of stability, despite mechanical agitation associated with installing the fixture, cleaning it or changing the light bulb(s).
Another principal object is to provide an assembly system with the foregoing advantages that also provides low shipping costs for the fixture and shipment in a mode that minimizes the likelihood of damage to the crystals.
Still another object is to provide the foregoing advantages with a high degree of ease of assembly and allows the ready replacement of a damaged crystal or crystals.
Yet another advantage is to provide an assembly system that reduces the cost of manufacture as compared to conventional bracket-and-suspended crystal ceiling fixtures.
A still further advantage is to provide an assembly system with all of the foregoing advantages which provides an assembled lighting fixture that has a highly "clean" and aesthetically pleasing appearance.